package Queue;

import java.util.Arrays;

/**
 * ClassName: Array
 * Package: Array
 *
 * @Author 马学兴
 * @Create 2023/11/30 14:40
 * @Version 1.0
 * Description:动态数组
 */
public class Array<E> {
    private E[] data;
    private int size;

    public Array(int capacity) {
        data = (E[]) new Object [capacity];
        size = 0;
    }

    public Array() {
        this(10);
    }
    public int getSize(){
        return size;
    }
    public int getCapacity(){
        return data.length;
    }
    public boolean isEmpty(){
        return size==0;
    }
    public void addLast(E e){
        /*if (size== data.length){
            throw new IllegalArgumentException(("addlast failed"));
        }
        data[size]=e;
        size++;*/
        add(size,e);
    }
    public void addFirst(E e){
        add(0,e);
    }
    public void add(int index,E e){//在第index位置插入e
        if (index<0||index>size){
            throw new IllegalArgumentException(("addlast failed"));
        }
        if (size== data.length){
            resize(2* data.length);
        }
        for (int i = size-1; i >=index ; i--) {//从数组的末尾开始遍历到索引index，
            // 在每次循环中将当前元素往后移动一个位置
            data[i+1]=data[i];
        }
        data[index]=e;
        size++;
    }
     public E get(int index){
        if (index<0&&index>=size){
            throw new IllegalArgumentException("get failed");
        }
        return data[index];
    }
    public E getLast(){
        return get(size-1);
    }
    public E getFirst(){
        return get(0);
    }
    void set(int index,E e){
        if (index<0&&index>=size){
            throw new IllegalArgumentException("get failed");
        }
        data[index]=e;
    }
    public boolean contains(E e){
        for (int i = 0; i < size; i++) {
            if (data[i].equals(e)){
                return true;
            }
        }
        return false;
    }
    public int find(E e){
        for (int i = 0; i < size; i++) {
            if (data[i].equals(e)){
                return i;
            }
        }
        return -1;
    }
    public E remove(int index){//
        if (index<0||index>size){
            throw new IllegalArgumentException(("addlast failed"));
        }
       E ret=data[index];
        for (int i = index+1; i <size ; i++) {
            data[i-1]=data[i];
        }
        size--;
        if (size== data.length/2){
            resize(data.length/2);
        }
        return ret;
    }
    public E removeFirst(){
       return remove(0);
    }
    public E removeLast(){
        return remove(size-1);
    }
    public void removeElement(E e){//删除已知元素
        int index=find(e);
        if (index!=-1){
            remove(index);
        }
    }

    @Override
    public String toString() {
        return "Array{" +
                "data=" + Arrays.toString(data) +
                ", size=" + size +
                '}';
    }
    private void resize(int newCapacity){
        E[] newData=(E[]) new Object[newCapacity];
        for (int i = 0; i < size; i++) {
            newData[i]=data[i];
        }
        data=newData;
    }
}
